The invention relates to a process and an installation for producing crystalline dextrose monohydrate.
It is known to prepare crystalline dextrose monohydrate by cooling dextrose-rich syrups in the presence of dextrose crystals which play the role of crystallization seed.
Known processes provide for the simultaneous employment of several devices of the malaxation type, arranged horizontally or vertically; these devices are equipped with stirring means and with means for regulating the temperature adapted to establish a temperature gradient decreasing in the mass subjected to crystallization, which is comprised by the syrup and the seed.
The last developments of these processes are reflected particularly by U.S. Pat. No. 4,357,172, filed the Dec. 16, 1980 and assigned to the Company CPC INTERNATIONAL INC., which provides a preparation in two steps; thus a first step, with continuous operation, provides, at the outlet from a first malaxator, a mixture of syrup and crystals relatively little enriched in crystals, denoted in the technique by the expression "poor phase massecuite"; the latter is then transferred in the second step to at least one second malaxator with discontinuous operation and providing a mixture highly enriched in crystals which is denoted by the expression "rich phase massecuite"; it is from the latter that the dextrose crystals are finally recovered.
These processes do not give entire satisfaction either from the point of view of productivity per unit volume of equipment or from that of the energy balance.
Now, to meet the always more severe constraints, particularly in the economic field, Applicants have sought to develop a process and an installation of the type concerned which responds better than those already existing to the various desiderata of practice, in particular precisely from the point of view of productivity of the crystallization operation per unit volume of equipment used and of the energy balance.